DS+: a method for the identification of cluster substructures

Abstract

The study of cluster substructures is important for the determination of the cluster dynamical status, assembly history, and the evolution of cluster galaxies, and it allows to set of constraints on the nature of dark matter and cosmological parameters. We present and test DS+, a new method for the identification and characterization of group-sized substructures in clusters. Our new method is based on the projected positions and line-of-sight velocities of cluster galaxies, and it is an improvement and extension of the traditional method of Dressler & Shectman (1988). We test it on cluster-size cosmological halos extracted from the IllustrisTNG simulations, with virial masses $14\lesssim \log ({\mathrm{M}}_{200}/{\mathrm{M}}_{\odot })\lesssim 14.6$, that contain on average $\sim 190$ galaxies. We also present an application of our method on a real data set, the Bullet cluster. DS+ is able to identify $\sim 80\%$ of real group galaxies as members of substructures, and at least 60\% of the galaxies assigned to substructures belong to real groups. The physical properties of the real groups are significantly correlated with those of the corresponding detected substructures, albeit with significant scatter, and overestimated on average. Application of the DS+ method to the Bullet cluster confirms the presence and main properties of the high-speed collision and identifies other substructures along the main cluster axis. DS+ proves to be a reliable method for the identification of substructures in clusters. The method is made freely available to the community as a Python code.

arXiv comment13 pages, 8 figures, accepted for publication in A&A

References in corpus (115)

• Planck 2015 results. XIII. Cosmological parameters
• A Universal Density Profile from Hierarchical Clustering
• E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Simulating Galaxy Formation with the IllustrisTNG Model
• First results from the IllustrisTNG simulations: matter and galaxy clustering
• First results from the IllustrisTNG simulations: the stellar mass content of groups and clusters of galaxies
• First results from the IllustrisTNG simulations: the galaxy color bimodality
• Properties of galaxies reproduced by a hydrodynamic simulation
• Direct constraints on the dark matter self-interaction cross-section from the merging galaxy cluster 1E0657-56
• Dark matter halo concentrations in the Wilkinson Microwave Anisotropy Probe year 5 cosmology
• The merger rate of galaxies in the Illustris Simulation: a comparison with observations and semi-empirical models
• Concentration, Spin and Shape of Dark Matter Haloes as a Function of the Cosmological Model: WMAP1, WMAP3 and WMAP5 results
• Weak lensing mass reconstruction of the interacting cluster 1E0657-558: Direct evidence for the existence of dark matter
• A Textbook Example of a Bow Shock in the Merging Galaxy Cluster 1E0657-56
• Structure and Dynamics of the Coma Cluster
• Strong and weak lensing united III: Measuring the mass distribution of the merging galaxy cluster 1E0657-56
• The C4 Clustering Algorithm: Clusters of Galaxies in the Sloan Digital Sky Survey
• Images, structural properties and metal abundances of galaxy clusters observed with Chandra ACIS-I at 0.1<z<1.3
• Creation of cosmic structure in the complex galaxy cluster merger Abell 2744
• The relation between velocity dispersion and mass in simulated clusters of galaxies: dependence on the tracer and the baryonic physics
• The speed of the `bullet' in the merging galaxy cluster 1E0657-56
• On the efficiency and reliability of cluster mass estimates based on member galaxies
• A comparison of the galaxy populations in the Coma and distant clusters: the evolution of k+a galaxies and the role of the intracluster medium
• The Integrated Sunyaev-Zeldovich Effect as the Superior Method for Measuring the Mass of Clusters of Galaxies
• COSMOLOGICAL CONSTRAINTS FROM CLUSTER X-RAY MORPHOLOGIES
• MAMPOSSt: Modelling Anisotropy and Mass Profiles of Observed Spherical Systems. I. Gaussian 3D velocities
• Quantifying the Morphologies and Dynamical Evolution of Galaxy Clusters. I. The Method
• Group-cluster merging and the formation of starburst galaxies
• The Extraordinary Amount of Substructure in the Hubble Frontier Fields Cluster Abell 2744
• The ESO Nearby Abell Cluster Survey. XI. Segregation of cluster galaxies and subclustering
• A non-parametric and scale-independent method for cluster analysis II: the multivariate case
• Simulating the Bullet Cluster
• The dynamical state of the Coma cluster with XMM-Newton
• Substructure and dynamical state of 2092 rich clusters of galaxies derived from photometric data
• Substructure in Clusters and Central Galaxy Peculiar Velocities
• The Dynamical Status of the Cluster of Galaxies 1E0657-56
• The universal distribution of halo interlopers in projected phase space. Bias in galaxy cluster concentration and velocity anisotropy?
• Weak lensing mass reconstructions of the ESO Distant Cluster Survey
• A massive blow for $\Lambda$CDM $-$ the high redshift, mass, and collision velocity of the interacting galaxy cluster El Gordo contradicts concordance cosmology
• Substructures in WINGS clusters
• The Three Hundred Project: Dynamical state of galaxy clusters and morphology from multi-wavelength synthetic maps
• The concentration-mass relation of clusters of galaxies from the OmegaWINGS survey
• Searching for cluster substructure using APM and ROSAT data
• Multimodality in galaxy clusters from SDSS DR8: substructure and velocity distribution
• Gravitational Shear, Flexion and Strong Lensing in Abell 1689
• The Cluster-Merger Shock in 1E 0657-56: Faster than the Speeding Bullet?
• Dynamical state and star formation properties of the merging galaxy cluster Abell 3921
• X-ray Substructure Studies of Four Galaxy Clusters using XMM-Newton Data
• Optical Substructure and BCG Offsets of Sunyaev-Zel'dovich and X-ray Selected Galaxy Clusters
• Searching for rotating galaxy clusters in SDSS and 2dFGRS
• Morphology parameters: substructure identification in X-ray galaxy clusters
• Non-parametric Reconstruction of Abell 2218 from Combined Weak and Strong Lensing
• The Dynamics of Merging Clusters: A Monte Carlo Solution Applied to the Bullet and Musket Ball Clusters
• Multiple merging events in Abell 521
• Merging Cluster Collaboration: A Panchromatic Atlas of Radio Relic Mergers
• Fabry-Perot Measurements of the Dynamics of Globular Cluster Cores: M15 (NGC~7078)
• Substructure Analysis of Selected Low Richness 2dFGRS Clusters of Galaxies
• Internal dynamics of the z sim 0.8 cluster RX J0152.7-1357
• Constrained Simulation of the Bullet Cluster
• The Impact of ICM Substructure on Ram Pressure Stripping
• Structures in Galaxy Clusters
• Substructure and Scatter in the Mass-Temperature Relations of Simulated Clusters
• The Northern Sky Optical Cluster Survey III: A Cluster Catalog Covering Pi Steradians
• Mass Estimation of Merging Galaxy Clusters
• A joint SZ-Xray-optical analysis of the dynamical state of 288 massive galaxy clusters
• SPIDER IX - Classifying Galaxy Groups according to their Velocity Distribution
• Robust quantitative measures of cluster X-ray morphology, and comparisons between cluster characteristics
• Dynamical state of galaxy clusters evaluated from X-ray images
• The Sloan Great Wall. Rich clusters
• The eROSITA Final Equatorial-Depth Survey (eFEDS): Characterization of Morphological Properties of Galaxy Groups and Clusters
• Accretion of Galaxy Groups into Galaxy Clusters
• NoSOCS in SDSS III - The interplay between galaxy evolution and the dynamical state of galaxy clusters
• X-ray Galaxy Clusters in NoSOCS: Substructure and the Correlation of Optical and X-ray Properties
• Galaxy pre-processing in substructures around z$\sim$0.4 galaxy clusters
• Statistics and implications of substructure detected in a representative sample of X-ray clusters
• The rise and fall of a challenger: the Bullet Cluster in $\Lambda$ Cold Dark Matter simulations
• Evidence for galaxies being pre-processed before accreted into clusters
• Weak lensing study of 16 DAFT/FADA clusters: substructures and filaments
• A New Method to Quantify X-ray Substructures in Clusters of Galaxies
• The Most Massive galaxy Clusters (M2C) across cosmic time: link between radial total mass distribution and dynamical state
• Identification of galaxy cluster substructures with the Caustic method
• Cluster Morphologies as a Test of Different Cosmological Models
• Characterizing the Properties of Clusters of Galaxies as a Function of Luminosity and Redshift
• Supercluster A2142 and collapse in action - infalling and merging groups and galaxy transformations
• Internal dynamics of Abell 2254: a merging galaxy cluster with a clumpy, diffuse radio emission
• Evolutionary phases of merging clusters as seen by LOFAR
• The Corona Borealis supercluster: connectivity, collapse, and evolution
• The Three Hundred: Cluster Dynamical States and Relaxation Time Scale
• Suppressed radio emission in supercluster galaxies: enhanced ram pressure in merging clusters?
• Simulated Analogs of Merging Galaxy Clusters Constrain the Viewing Angle
• Bullet Clusters in the MareNostrum Universe
• The Three Hundred project: Galaxy groups do not survive cluster infall
• Quantifying substructures in {\it Hubble Frontier Field} clusters: comparison with $\Lambda CDM$ simulations
• The Dynamics of Abell 2125
• Investigating the Projected Phase Space of Gaussian and Non-Gaussian Clusters
• Leavers and remainers: Galaxies split by group-exit
• MeerKAT's View of the Bullet Cluster 1E 0657-55.8
• Unveiling the merger dynamics of the most massive MaDCoWS cluster at $z=1.2$ from a multi-wavelength mapping of its intracluster medium properties
• The Distribution of Dark and Luminous Matter in the Unique Galaxy Cluster Merger Abell 2146
• An Examination of the Optical Substructure of Galaxy Clusters Hosting Radio Sources
• $Suzaku$ and $XMM-Newton$ observations of a newly-discovered early-stage cluster merger 1E2216.0-0401 and 1E2215.7-0404
• Identifying dynamically young galaxy groups via wide-angle tail galaxies: A case study in the COSMOS field at z=0.53
• Velocity dispersions and cluster properties in the SARS (Southern Abell Redshift Survey) clusters. Paper II
• Blooming Trees: Substructures and Surrounding Groups of Galaxy Clusters
• The puzzling merging cluster Abell 1914: new insights from the kinematics of member galaxies
• The dynamic stage of clusters and its influence on the stellar populations of galaxies
• The influence of mergers on the cluster temperature function and cosmological parameters derived from it
• Studying galaxy cluster morphological metrics with Mock-X
• Locations and Morphologies of Jellyfish Galaxies in A2744 and A370
• Multi-object spectroscopy of CL1821+643: a dynamically relaxed cluster with a giant radio halo?
• An approximate theory for substructure propagation in clusters
• "Observing" Unrelaxed Clusters in Dark Matter Simulations
• Two merging galaxy clusters with very hot shock fronts observed shortly before pericentric passage
• Morphology of relaxed and merging galaxy clusters. Analytical models for monolithic Minkowski functionals

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